The invention generally relates to dispensers, and more specifically, to dispensers for dispensing sheet material having an adjustable dispensing port.
Dispensers for rolls or stacks of sheet material have an exit port which usually permits one sheet material at a time to be dispensed therethrough. Problems exist when an exit port has only a single diameter through which a sheet material is dispensed to a user. This results in too many sheets or too few sheets dispensed through the exit port, depending upon the diameter of the exit port and the characteristics of the sheet material. Therefore, dispensers have been provided which include various apparatus for addressing the problem.
One dispenser, U.S. Pat. No. 5,370,338 to Lewis, which is hereby incorporated by reference herein, discloses a variable orifice centerflow dispenser that provides a movable disk over an exit port which has several different sizes of orifices formed in the disk. A specific orifice in the disk is selected by an operator when a roll of sheet material is positioned in the dispenser. The limited selection of orifice diameters, however, has disadvantages as well. Another dispenser, U.S. Pat. No. 5,749,492 to Petterson, which is hereby incorporated by reference herein, discloses a sheet dispenser which uses two arcuately-shaped plates which are brought together to provide an adjustable opening over an exit port. This type of dispenser also has disadvantages.
When an apparatus positioned over an exit port has an opening having a diameter that is too large, an excessive, wasteful number of sheets may be dispensed to a user. When such an apparatus has an opening having a diameter that is too small, a sheet may tear off inside of the dispenser without a leading edge extending through the opening and the exit port, making the remaining sheets in the roll unavailable to a user. In addition, when an apparatus has an elliptically-shaped opening through which sheets are dispensed, the sheets may become caught or tear off in the apparatus due to snagging of the sheet material within the narrowing at each end of the elliptically-shaped opening while being pulled through the opening by a user.
Additional problems are also created because sheet material products from various manufacturers may be used in the dispenser, and each product has its own characteristics. That is, the caliper and basis weight of the sheet material of each product will likely be different. Further, the machine direction tensile of the sheet material will vary in different products. Moreover, the tab strength of each sheet material will also vary product-to-product. These differing characteristics of each product require an operator to adjust the diameter of an opening in an apparatus adjacent the exit port for each particular product contained therein. When the choice of diameter of the opening of the apparatus is limited to only a few choices of an opening diameter, or when generally elliptically-shaped openings are provided, it can result in either waste by dispensing too many sheets to a user, or lack of use and user aggravation when sheet material tears off inside of the dispenser and is not dispensed through an apparatus opening and the exit port. Further, when sheets snag or tear apart when pulled through an apparatus having an elliptically-shaped opening, waste and/or user aggravation is again the result.
In addition, when an operator has adjusted an apparatus in a dispenser to properly dispense a sheet material through the exit port, it can be difficult for the operator to push the sheet material through an opening having a small diameter in such an apparatus. Therefore, reloading of sheet material provides difficulties for an operator each time new sheet material is disposed in the dispenser.
It would be advantageous to have a dispenser for sheet material which is rolled, or sheet material which is stacked, which permits an operator to choose from any one of a large number of diameters of an opening formed by an apparatus positioned near or over the exit port. Such an apparatus would provide an opening whose diameter is incrementally increased or decreased, within a range, to accommodate the characteristics of different sheet material products. Such a dispenser would permit the operator to quickly and easily optimize the diameter of the apparatus opening to the characteristics of a specific product contained therein so that sufficient sheets are dispensed to a user, and neither waste nor user aggravation occurs. In addition, the apparatus would form an opening configured to reduce or eliminate snagging, tearing, or ripping of sheet material when it moves through the apparatus opening and exit port.
Ease in loading new sheet material without having to re-adjust a diameter of an opening of an apparatus for the same product would also be advantageous. Therefore, the dispenser would also include additional components which cooperate with the apparatus to quickly and easily increase the diameter of the opening of the apparatus to allow an operator to easily load sheet material and dispose a leading edge of a sheet through the apparatus opening and exit port. Yet, such an apparatus and additional components would decrease the diameter of the opening to its pre-adjusted diameter for dispensing just as quickly and easily, once sheet material was disposed therein, to provide proper dispensing of the newly loaded sheet material through the apparatus opening and exit port.
As used herein, the term xe2x80x9ccaliperxe2x80x9d refers to the thickness measurement of a sheet taken under constant force. The caliper may be determined using test method number TAPP 411-OM-89.
As used herein, the term xe2x80x9cbasis weightxe2x80x9d (hereinafter xe2x80x9cBWxe2x80x9d) is the weight per unit area of a sample and may be reported as gram-force per meter squared and may be hereinafter calculated using test procedure ASTM D3776-96.
As used herein, the term xe2x80x9cmachine directionxe2x80x9d (hereinafter xe2x80x9cMDxe2x80x9d) is the direction of a material parallel to its forward direction during processing.
As used herein, the term xe2x80x9cmachine direction tensilexe2x80x9d (hereinafter MDT) is the breaking force in the machine direction required to rupture a specimen. The results may be reported as gram-force and abbreviated as xe2x80x9cgfxe2x80x9d. The MDT may be determined using test method number ASTM D5035-95.
As used herein, the term xe2x80x9ctab strengthxe2x80x9d is the breaking force in the machine direction required to rupture a sheet product along its perforations. The results may be reported as gram-force and abbreviated as xe2x80x9cgfxe2x80x9d.
As used herein, the term xe2x80x9cexit portxe2x80x9d is the opening in a housing of a dispenser for the passage of sheet material.
As used herein, the term xe2x80x9ciris diaphragmxe2x80x9d means three or more iris blades supported for movement by a cam gear which cooperate to forming an iris diaphragm which forms an opening having a diameter that is incrementally adjustable within a range of movement of the iris blades so that when the iris blades are moved incrementally and simultaneously toward each other, the diameter of the opening of the iris diaphragm is decreased; when the iris blades are moved incrementally and simultaneously away from each other, the diameter of the opening of the iris diaphragm is increased. In this manner, the iris diaphragm is capable of providing any one of a great number of diameters of the opening therein within the range. The iris diaphragm forms a near closure, that is, a smaller opening at a low end of the range, and, at the high end of the range, forms an opening having an increased diameter sized generally at least about the diameter of the exit port.
As used herein, the term xe2x80x9ccenterflow rollxe2x80x9d or xe2x80x9ccenterflow roll productxe2x80x9d means sheet material wound cylindrically about a center, but permitting the removal of material from the center. Desirably, as the centerflow roll is consumed, sheet material eventually dispenses from the roll""s periphery. Dispensing of centerflow roll products are described in numerous patents, such as, but not by way of limitation, U.S. Pat. No. 5,370,338 to Lewis and U.S. Pat. No. 6,082,663 to Tramontina et al.
As used herein, the term xe2x80x9csheet materialxe2x80x9d means a material that is thin in comparison to its length and breadth. Generally speaking, sheet materials should exhibit a relatively flat planar configuration and be flexible to permit folding, rolling, stacking, and the like. Exemplary sheet materials include, but are not limited to, paper tissue, paper towels, label rolls, or other fibrous, film, polymers, or filamentary products.
As used herein, the term xe2x80x9cfastenersxe2x80x9d means devices that fasten, join, connect, secure, hold, or clamp components together. Fasteners include, but are not limited to, screws, nuts and bolts, rivets, snap-fits, tacks, nails, loop fasteners, and interlocking male/female connectors, such as fishhook connectors, a fish hook connector includes a male portion with a protrusion on its circumference. Inserting the male portion into the female portion substantially permanently locks the two portions together.
As used herein, the terms xe2x80x9cincrementallyxe2x80x9d, xe2x80x9cincrementalxe2x80x9d, and/or xe2x80x9cincrement(s)xe2x80x9d mean a change in measurement, i.e., an increase or decrease in the diameter of an opening formed by the iris diaphragm in a range of about 0.5 millimeters (hereinafter xe2x80x9cmmxe2x80x9d or xe2x80x9cmmsxe2x80x9d) in one increment to at least about the diameter of the exit port, for example, in the present embodiment, about 8.0 centimeters (hereinafter xe2x80x9ccmxe2x80x9d or xe2x80x9ccmsxe2x80x9d) in one increment. For example, the diameter of the opening of the iris diaphragm to dispense a two ply paper towel or wiper is about 1.3 cms to about 1.7 cms. A diameter within the range, i.e., 1.5 cms, may be obtained by using one increment of 1.5 cms, or, alternatively, a number of equal and/or unequal increments that reached the desired diameter of 1.5 cms. The measurement of either end of the range for the increments is limited only by the limitation of size and movement of the iris blades relative to their operation in the iris diaphragm.
As user herein, the term xe2x80x9ccouplexe2x80x9d includes, but is not limited to, joining, connecting, fastening, linking, or associating two things integrally or interstitially together.
In one aspect of the invention, a dispenser adapted to dispense sheet material is provided, and includes a housing. The housing includes at least an exit port and is configured to support sheet material therein. An iris diaphragm including at least three iris blades is positioned on the housing. The iris diaphragm is supported for movement to form an opening having a diameter incrementally adjustable within a range. The iris diaphragm is configured to be adjusted to any one of a plurality of opening diameters within the range. The iris diaphragm is also configured to permit the diameter of the opening to be adjusted for each product-type of sheet material positioned in the dispenser to provide controlled dispensing of the sheet material from the dispenser.
In another aspect of the invention, an apparatus adapted for use with a dispenser housing for sheet material is provided. The apparatus is configured to cooperate with an opening formed in the dispenser housing to control the flow of sheet material disposed in the dispenser housing and extending through the opening therein. The apparatus includes a platform formed to include an exit port, and an iris diaphragm. The iris diaphragm includes a plurality of iris blades positioned on the platform and supported for movement to form an opening having a diameter incrementally adjustable within a range. The iris diaphragm is configured to be adjusted to any one of a plurality of opening diameters within the range. In addition, the iris diaphragm is configured to permit the diameter of the opening formed therein to be adjusted for each product-type of sheet material positioned in a dispenser housing to provide controlled dispensing of the sheet material from the apparatus and through the exit port.
A method of installing a sheet material product into a dispenser is provided. A platform provided in a housing of a dispenser having an exit port is accessed. A portion of a slide assembly positioned in the dispenser is moved at least partially away from the dispenser. The slide assembly is operatively engaged to at least a portion of an iris diaphragm which is supported by a portion of the housing, and the movement of the slide assembly causes movement of the iris diaphragm such that a diameter of an opening formed by the iris diaphragm is increased to provide a loading position adjacent the exit port. A sheet material product is disposed onto the platform. The platform is formed to include an opening positioned at least partially below the product, and the opening is in communication with the opening formed by the iris diaphragm and the exit port forming a channel for the movement of sheet material therethrough. A leading edge of the sheet material is pushed through the channel and the exit port. The portion of the slide assembly is moved toward the dispenser, the slide assembly causing movement of the iris diaphragm such that the diameter of the opening formed thereby is moved to its pre-adjusted diameter providing a dispensing position.
In another aspect of the invention another method of installing sheet material into a dispenser is provided. A dispenser housing configured to support sheet material therein and having an iris diaphragm and an exit port is provided. The diameter of an opening in the iris diaphragm is incrementally adjusted such that the opening is sized to permit an effective number of sheet materials to be dispensed through the opening and the exit port such that the sheet material neither excessively dispensed nor under dispensed.
In yet another aspect of the invention, a dispenser adapted to dispense sheet material is provided. The dispenser comprises a housing including a platform having an exit port therein and configured to support sheet material therein. The dispenser also includes at least an iris diaphragm for controlling the movement of sheet material disposed in the housing through the exit port.